nonspecific immunoprecipitation control - (Aug/08/2009 )
I'm going to do immunoprecipitation on human ovarian cell line by a rabbit polyclonal antibody. I have been told to use an irrelevant polyclonal antibody as a nonspecific polyclonal antibody. It is written in protocole to use an antibody to an epitope that is not present in the cell lysate as a control but I don't know what to use.
Are you pulling down an endogenous protein? Have the cells been treated in any way (transfected, etc.)?
Without more information, the first thing that came to my mind was to use a rabbit polyclonal antibody against a myc- or flag-tag, GFP or luciferase, since none of these should be endogenously expressed by human ovarian cells.
Alternatively, you could use a rabbit polyclonal antibody that recognizes a mouse- (or any non-human-) specific antigen. In this case, make sure the antibody you use does not cross-react with the human version of the protein. This information should be available on the vendor's website.